Commit 55e5c285 breaks CPU not found return value, and returns
CPU corresponding to the last non NULL env.
Fix it by returning CPU only if env is not NULL, otherwise CPU is
not found and function should return NULL.
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>